With the rapid proliferation of network-related technologies, more and more users routinely carry out online transactions to manage business and/or personal affairs using online services, such as online banking, online stock brokerage, online shopping, etc. In the current document, an online transaction refers to a transaction performed at least in part over a network, at least a portion of which is publicly accessible, such as the Internet, a combination of the Internet and an intranet, etc. In online transactions, sensitive personal information may be submitted over the publicly accessible network via legitimate web pages. Although online transactions provide great convenience to users in general, unfortunately, criminals may attempt to steal sensitive personal information over the network from some unsuspecting users. Once the criminals obtain such information, they may use the information to commit identity thefts to steal thousands of dollars from the victims.
One common way to steal information online is phishing. Phishing in general is to steal information online by trickery. A phisher may set up a counterfeit web page, also referred to as a spoofed web page. The counterfeit web page may be similar to a legitimate web page such that the counterfeit web page may trick unsuspecting users to provide their personal information via the counterfeit web page to the criminal. For instance, the counterfeit web page may have a uniform resource locator (URL) similar to the legitimate web page such that a user misspelling the URL of the legitimate web page may be directed to the counterfeit web page. Alternatively, the criminal may send electronic mail posing as the entity running the legitimate web page to users with a link to the counterfeit web page in order to scam the users. The counterfeit web page may request personal information, such as passwords to financial accounts (e.g., bank accounts, brokerage accounts, retirement saving accounts, etc.), credit card numbers, social security numbers, bank account numbers, etc.
Currently, some browser vendor maintains a central list of the URLs of some known counterfeit web pages. When a browser attempts to access a web page, the browser may access the central list to check if the URL of the web page is in the central list. If the URL is in the central list, then the web page is a known counterfeit web page and the browser may block access to the web page. The browser vendor may periodically update the central list with URLs of newly found counterfeit web pages.
However, users may find the above protection against phishing inconvenient because the users have to constantly rely on support from the browser vendor. Furthermore, as time goes by, the central list may grow substantially, and it may take a long time to access the central list. Moreover, the central list may not include newly created counterfeit web pages not yet identified because no one has reported the newly created counterfeit web pages to the browser vendor yet. This may result in a security loophole, which criminals may exploit.